1. Field of the Invention
The present invention relates to a rear suspension apparatus for a high speed vehicle having a first and a second driven ground engaging wheel.
More specifically, the present invention relates to a non independent rear suspension apparatus for a racing car or dragster having a first and a second driven ground engaging wheel.
2. Background Information
In motor racing, racing cars are designed to achieve the greatest possible rate of acceleration. Often, the difference between winning or losing a race depends on how rapidly the racing car is able to accelerate on a straight section of the racetrack.
With a racing car or dragster having a power source for driving the rear wheels of the vehicle, the power is supplied to the rear wheels by a power train which includes a rear axle having a differential gear assembly. During acceleration on a straight section of the racetrack, power is supplied to an input of the differential gear assembly which is designed to generate an equal rotational force to both of the driven rear wheels.
However, there is also a tendency under acceleration for the whole rear axle to rotate around an axis extending through the input of the differential gear assembly. Such rotational tendency of the rear axle urges a driven first rear wheel towards the ground while tending to lift the second driven wheel away from the ground. Therefore, under these circumstances, the second wheel tends to spin while a lesser rotational force is applied through the differential gear assembly to the first wheel in an attempt to compensate for the wheel slip of the second wheel. Therefore, the full advantage of the available power is not uniformly applied to both wheels for attaining a maximum acceleration of the vehicle.
Although relatively complex limited slip differential gear assemblies have been devised to increase acceleration, such assemblies increase the weight of the rear axle and do not fully compensate for the unequal ground contact force between the respective driven wheels.
The present invention overcomes the aforementioned problem by the provision of truck arms having differential hardness. More specifically, the hardness of the second truck arm which is associated with the second driven wheel is greater than the hardness of the first truck arm associated with the first driven wheel. Accordingly, during acceleration, the tendency for the second wheel to lift is restrained because the second truck arm is of harder and therefore less resilient steel.
Accordingly, in the arrangement according to the present invention, when the second wheel and tire thereon tends to lift upwardly away from the track, such upward movement is resisted by the increased hardness and lesser resilience of the associated second arm. Consequently, the rotational force applied by the differential gear assembly through the second drive shaft applies a rotational force to the second wheel for applying an acceleration to the second wheel which is fully utilized by the maintained ground contact of the second wheel while an equal rotational force is at the same time applied to the first wheel.
Additionally, by compensating in the aforementioned manner by fabricating the arms of different hardness steels, such arrangement does not interfere with the application by the differential gear assembly of differential power to the respective wheels during cornering.
Therefore, it is a primary feature of the present invention to provide a rear suspension apparatus that overcomes the problems associated with the prior art arrangements.
Another feature of the present invention is the provision of a rear suspension apparatus that enhances the acceleration of the vehicle.
Other features and advantages of the present invention will be readily apparent to those skilled in the art by a consideration of the detailed description of a preferred embodiment of the present invention contained herein.